1. Field of the Invention
The present invention relates to a lock device for an electronic appliance, such as a portable computer, with a lower housing and an upper housing hinged to the lower housing, more particularly to a lock device for locking the upper housing to the lower housing of the electronic appliance with a selected one of two opposite sides of the upper housing facing the lower housing, and to an electronic appliance incorporating the lock device.
2. Description of the Related Art
FIGS. 1 and 2 illustrate a conventional portable computer 9 which includes a lower housing 91 with a top side 912 installed with a keyboard unit, and an upper housing 92 with a screen side 922 installed with a display unit. The upper housing 92 has a lower edge portion 921 hinged to a rear edge portion 911 of the lower housing 91 such that the upper housing 92 is turnable toward and away from the top side 912 of the lower housing 91 for covering and uncovering the top side 912 of the lower housing 91. The upper housing 92 is further rotatable about a vertical rotary axis 93 when uncovered from the lower housing 91 and when disposed at an upright position perpendicular to the lower housing 91. FIG. 1 shows the portable computer 9 in an uncovering state with the screen side 922 of the upper housing 92 facing the lower housing 91. Referring to FIG. 2, when the upper housing 92 is rotated about the vertical axis 93 by 180 degrees, the back side 923 is turned forwardly to face the top side 912 of the lower housing 91.
However, a lock device provided on the portable computer 9 includes a latch member 94 mounted on the screen side 922 of the upper housing 92, and a latch engaging groove 913 formed in the top side 912 of the lower housing 91 for engaging the latch member 94. As such, the upper housing 92 can be locked to the lower housing 91 only when the screen side 922 faces the top side 912 of the lower housing 91. This undesirably limits the utility of the vertically rotatable upper housing 92 of the portable computer 9.
Therefore, the object of the present invention is to provide a lock device for locking an upper housing to a lower housing of an electronic appliance with a selected one of two opposite sides of the upper housing facing the lower housing.
According to the present invention, there is provided a lock device for an electronic appliance which includes a lower housing with a horizontal top side wall and front and rear edge portions, and an upper housing that has a lower edge portion hinged to the rear edge portion of the lower housing, an upper edge, and opposite first and second side walls disposed on opposite first and second sides of the upper housing. The upper housing is turnable relative to the lower housing with either of the first and second side walls facing the lower housing. The lock device includes a mounting unit, an actuating unit, and a latch unit. The mounting unit is adapted to be mounted on the upper housing and to be disposed at the upper edge of the upper housing. The mounting unit includes an elongated mounting wall transverse to the first and second side walls of the upper housing and having two opposite longitudinal edges, and parallel first and second flanges extending respectively along the longitudinal edges of the mounting wall and transverse to the mounting wall. The first and second flanges are adapted to be disposed respectively on the first and second sides of the upper housing. The first flange is formed with a first latch hole. The second flange is formed with a second latch hole. The actuating unit is mounted on the mounting wall, and is disposed between the first and second flanges. The actuating unit has a first actuating portion disposed adjacent to the first flange, and a second actuating portion disposed adjacent to the second flange. The actuating unit includes a magnet that is disposed between the first and second actuating portions. The actuating unit is normally disposed in a non-actuating position, in which the first actuating portion is displaced from the first latch hole, and in which the second actuating portion is displaced from the second latch hole. The latch unit is adapted to be mounted on the lower housing adjacent to the front edge portion and the top side wall. The latch unit includes a latch member made of a magnetic material. The latch member is normally disposed in an unlocking position, in which the latch member is retracted into the top side wall of the lower housing. The latch member is movable to a locking position by virtue of magnetic attraction applied by the magnet when the upper housing covers the top side wall of the lower housing. The latch member projects upwardly relative to the top side wall of the lower housing, and engages an adjacent one of the first and second latch holes when moved to the locking position. The actuating unit is operable for moving relative to the mounting wall to an actuating position, in which the first actuating portion is moved proximate to the first latch hole, and in which the second actuating portion is moved proximate to the second latch hole. The first actuating portion is moved toward the latch member, and pushes the latch member for disengaging the latch member from the first latch hole when the actuating unit is moved to the actuating position while the upper housing covers the top side wall of the lower housing with the first side wall facing the lower housing. The second actuating portion is moved toward the latch member, and pushes the latch member for disengaging the latch member from the second latch hole when the actuating unit is moved to the actuating position while the upper housing covers the top side wall of the lower housing with the second side wall facing the lower housing.